Isopropanolamine esters of 3-(3,5 di-t-butyl-4-hydroxyphenyl)propanoic acid

ABSTRACT

Esterified isopropanolamines of the formula,   WHEREIN N IS AN INTEGER OF 1 TO 3; R1 and R2 are independently hydrogen or alkyl having 1 - 18 carbon atoms provided that when n is 2, R2 is not present and when n is 3, both R1 and R2 are not present, have excellent stabilizing effect on organic substance, especially polyolefins. These esterified isopropanolamines are prepared by reacting an isopropanolamine derivative with Beta (3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid or a reactive derivative thereof.

United States Patent Sagawa et al.

[ NOV. 18, 1975 ISOPROPANOLAMINE ESTERS OF 3-[3,5

DI-T-BUTYL-4- HYDROXYPHENYLHROPANOIC ACID [75] Inventors: Seiji Sagawa, Kawachinagano;

Hiroyasu Itoi, Ibaragi; Kazuhiko Fujiyoshi, Toyonaka; Kazuyoshi Kagaya, Ibaragi, all of Japan [73] Assignee: Sumitomo Chemical Company, Ltd.,

Osaka, Japan 22 Filed: May6, 1974 21 Appl. No.: 467,229

4/1969 Dexter et a] 260/473 S FOREIGN PATENTS OR APPLICATIONS 1,001,098 8/1965 United Kingdom 260/473 S Japan OTHER PUBLICATIONS Ogata, C. A., 73, 133254u (1970).

Primary ExaminerJo hn F. Terapane Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher [57] ABSTRACT Esterified isopropanolamines of the formula,

wherein n is an integer of l to 3; R and R are independently hydrogen or alkyl having 1 18 carbon atoms provided that when n is 2, R is not present and when n is 3, both R and R are not present, have excellent stabilizing effect on organic substance, especially polyolefins. These esterified isopropanolamines are prepared by reacting an isopropanolamine derivative with ,B-(3,5-di-tert-butyl-4-hydroxypheny1)propionic acid or a reactive derivative thereof.

3 Claims,- No Drawings ISOPROPANOLAMINE ESTERS'IOF 343,5 DI-T-BIJTYL-4-HYDROXYPHENYLlPROPANOlC ACID This invention relates to novel stabilizersifor organic 5 Various stabilizers for organic substances, especially IQ I novel esterified"isopropanolamines having excellent stabilizing effect in organic substances, especiallyin p'olyolefins. It is another object of the present invention tdp rovide 'a process for preparing said esterified isofor polyolefins have been proposed. Polyolefins' are widely used in various fields as molded articles, pipes, film, fibers, etc. processed by compression, extrusion",

injection, spinning and the like for their excellent phys ical and chemical properties. But polyolefins such as 1.5 propanolainines with low costindustriaily. It is a ;fur polyethylene and polypropylene have, as is 'well known,

great defects in that ifpolyolefins are used alone, they are easily degraded oxidatively by heat or light during the processing and the use of processed articles so that selected from the group consisting of N -(lower alkyl),

4 ubtitutd flowe alkyl); '1 ,4-piperazinyl and alkaneamide having 2 24' carbonatom's, for stabilizing organic substances is disclosed in Japanese Pat. No. 42-22456 (22456/1967). Said ester is prepared from an ethanolamine derivative, but the total yield of the desired compound is low. Further said ester is insufficient in stabilizing effect for organic substances.

It is an object of the present invention to provide ther object of the present invention to provide a stabili i za'tion of organic substancs especially polyolefin,

using saidesterified isopropanolamine. Further objects and advan'tages of the present invention will be apparthey are decreased in molecular weight and sometimes 20 ent to one skilled in the art from the accompanying dis-- are colored or stinked, and mechanical strengths of them are decreased remarkably, which make commercial value of them lessen. In order to protectpolyolefinesfrom degradation, there are used, for example, 2,6-di-tert-butyl-p-cresol, 4,4-butylidene-bis-(6-tertbutyl-3-methylphenol), andthe like as stabilizer,-.-and 1, l ,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl )bu-,

tane, 1 ,3,5-trimethyl-2,4,6-tris( 3,5-di-tert-butyl-4- hydroxybenzyl)benzene,. n-octadecyl 3-(3,5-di-tertbutyl-4-hydroxyphenyl)propionate, and the like as heat stabilizer. But almost all the known stabilizers are insufcompatibility, non-staining property, divergency and the like. a A,

CH2 'CH 0 c CH2 cHg OH- closure and discussion. v

The present invention provides a novel compound of the formula,

wherein n is-an integer of l to 3; and R and R are independently hydrogen or alkyl having 1 .18 carbon 35 atoms provided that when n is 2, R is not present and when n is 3, both Ryand R are'not present. Among the compoundsof the formula (1-), favorable compounds are represented by the formula,

wherein R is as defined above, and n is an integer of 2 or 3, provided that when n is 3, R is not present; and v ficient for practical use in polyolefins in stabilization, 0 n is 2, R, is alkyl having one to 18 carbon atoms, preferably alkyl having six to 18 carbon atoms. The most favorable compound is represented by the formula,

Recently the use of an ester of the formula,

CH2 CH2 coo c11 CH2 i wherein Rand R" are independently alkyl having 4-8 i carbon atoms; and A is a bivalent substituted N group I CH; C--(" 3% 5 60 The-compound of the formula (I) has a structure sim- 5 group attached to'the B carbon atom with regard to the N atom.-Further, due-tosaid methyl group, the compou'nd 'of th e formula (l). isvery stable thermally and has no defects such as blooming when mixed with a polyolefin. I I I The compound of the formula (l)'can be prepared by reacting an isopropanolamine of the formula,

wherein R R and n are as defined above, with B- 3,5- di-tert-butyl-4-hydroxyphenyl)propionic acid or a reactive derivative thereof.

As the isopropanolamine of the formula (II), monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-methyldiisopropanolamine, N-ethyldiisopropanolamine, N-propyldiisopropanolamine, N-butyl- 'idiisopropanolamine, N-octyldiisopropanolamine, N- dodecyldiisopropanolamine,

N-octadecyldiisopropanolamine, N,N-dimethylmonoisopropanolamine, N,N-dioctylmonoisopropanolamine, monoisopropanolamine, N,N-dioctadecylrnonoisopropanolamine and N-methyl-N-octylisopropanolamine may be used preferably. These compounds may be obtained in low price.

As the reactive drivative of [3-( 3,5-di-tert-butyl-4- hydroxyphenyl)propionic acid, an alkyl ester thereof wherein the alkyl moiety has 1 8 carbon atoms such as methyl, ethyl, propyl, hexyl, isopropyl, tertiary butyl, octyl, an acid halide thereof or an acid anhydride thereof may be used.

The reaction may be carried out in the absence of a solvent or in the presence of an organic solvent such as benzene, toluene, xylene, methyl isobutyl ketone, dimethylformamide, or the like depending on the viscosity or slurry state of a mixture of the reactants. If necessary, a catalyst or a tertiary amine may be used in the reaction. Further the reaction may be carried out under an atmosphere of an inert gas such as nitrogen effectively, if necessary.

As the catalyst, conventional ones such as alkali metal alkoxides, caustic alkalis, alkali metals, alkali metal amides, hydrides of alkali metal or alkaline earth metal, hydrogenated alkali metal aluminum, aluminum borohydride, mineral acids such as sulfuric acid and hydrochloric acid, aromatic sulfonic acids such as paratoluenesulfonic acid may be used. The amount of the catalyst used may be 0.01 10% by weight, preferably 0.1 5.0% by weight, based on the total weight of the admixed reactans.

A tertiary amine may be mainly used as a removing agent for hydrogen halide if an acid halide is used as a starting material. An equivalent weight or more of the tertiary amine to the acid halide may be used. Examples of the tertiary amine or trimethylamine, triethylamine, pyridine, N,N-dimethylaniline, and the like.

In order to proceed the reaction favorably, it is preferable to remove a by-product such as water in the case of an acid, a corresponding alkanol in the case of an ester and a hydrogen halide in the case of an acid halide being used as a starting propionic acid derivative.

/3-(3,5-Di-tert-butyl-4-hydroxyphenyl)propionic acid or a reactive derivative thereof equivalent to the number of the hydroxyl group in anisopropanolamine of the formula (II) or in slightly excess may be used per equivalent weight of the isopropanolamine.

The reaction may be carried out at a temperature of from 0 to 360C, preferably from 0 to 220C under an atmospheric pressure or less.

N,N-didodecylv After the completion of the reaction, the reaction product is neutralized or filtered off, treated and purified using a conventional process to give the desired compound. 1

The compound of the formula (I) can be used effectively for stabilizing organic substances, such as polyolefins, halogenated vinyl polymers, copolymers of halogenated vinyl and unsaturated polymerizable compound, copolymers of acrylonitrile, butadiene and styrene, polyurethane, polyamides, polyesters, polyacetals, polycarbonates, polystyrene and natural and synthetic rubber. The compound of the present invention can also be applied for stabilizing lubricants, animal and vegetable oils, fat and oil, gasoline, mineral oil, fuels and alkylene glycols.

Examples of polyolefms are homopolymers or copolymers of ethylene, propylene, butene-l, isobutene, pentene-l, 4-methylpentene-l, and the like, or socalled petroleum resins obtained by polymerizing C or more cuts from petroleum cracking products.

The amount of the compound of the formula (I) to be added to the organic substance is 0.001 5 parts by weight, preferably 0.05 1 part by weight per parts by weight of the organic substance. When the compound of the formula (I) is added in an amount of less than 0.001 part by weight to the organic substance, the stabilizing effect is hardly expected, and almost no increased effect is expected when more than 5 parts by weight of the compound of the formula (I) is added to the organic substance.

Any compounding methods may be employed to obtain a uniform composition of the organic substance and the compound of the formula (I). For example, the desired composition may be prepared by dissolving the compound of the formula (I) in a solvent, having a low boiling point, adding the organic substance to the resulting mixture and then removing the solvent by vaporization, or by mixing the organic substance with the compound of the formula (I) in an extruder.

The compound of the formula (I) may be used together with other antioxidants, ultraviolet radiation absorbers, pigments, dispersing agents, plasticizers, fillers and the like additives.

When the compound of the formula (I) is used together with a thiodialkane acid ester of the formula,

wherein m is an integer of 1 to 6; R and R are independently a hydrocarbon radical having 4 20 carbon atoms, for stabilizing a polyolefin, more remarkably stabilized polyolefin composition can be obtained by synergistic effect. Examples of the compound of the formula (III) are dilaurylthio dipropionate, distearylthio dipropionate, dimyristylthio dipropionate, etc.

The thiodialkane acid ester is disclosed in Japanese.

In the following examples,'all partsand percent are by weight unless otherwisev Specified.

EXAMPLE 1 To a reactor, 64 g of methyl B-(3,5-di tert-butyl-4- hydroxyphenyl)propionate, 12.8 g of triisopropanolamine and 0.5 g of sodium methylate were charged simultaneously and heated at 135 4 1709Cfor 8 hours with stirring in'a stream of nitrogen. The evolved methanol was removed from the reactor. After cooling to room temperature, the reaction mixture was dissolved in benzene and washed with water three times to remove the sodium methylate used as catalyst. After removing the benzene by distillation, the residue was distilled at 140C/l mm Hg to yield 58 g ofN,N,N-tris-[B- (3,5-di-tert-butyl-4-hydroxyphenyl)propionyl] triisopropanolamine. Recrystallized from benzene-hexane system solvent, there were obtainedwhite crystals having a melting point of 147 150C.

Elementary analysis: C (7!) H (7r) N (9?) Calculated for C H o Nz 75.10 10.56 1.83 Found: 75.01

EXAMPLES 3 8 Various compounds within the formula (1) were'obtained using starting materials as listed in Table 1 under 1 the reaction conditions'as listed in Table 1. The results obtained were shown in Table 1.

Table 1 Starting materials Product Example R, R Reaction Reaction No. Y, X (Y )-,,N (Yd, temp. (C) time Solvent R R (hrs.) (ml) (g) (g) 3 Y Cl (Y NC, H (Y hNC H I 6.0 Benzene (64 g) (27g) 80-90 (200 m1) 4 Y OC H (Yr), NH (Y NH 100 120 12.0

5 Y Cl (Y h NC, H (YQ NC H;-, 2O 30 6.0 Toluene (64 g). (33 gl 80-90 (200 ml) CH CH; 30 40 8.0 Dimethyle v.' oc1-1a (Y' -)N (Y -)N folmamide V I CH CH (60-.40-mmHg) m1) s) (9 g) H a CR I7 1 RBI! 7 Y,-0c1-1, -(Y,-)-N (Y -)-N 140- 150 12.0 f

- a i-r n n I I 1 g) (29 g) 8 (Y,-OH (Y ');NCH (Y;,-);NCH;, 1 10 l 15 10.0 Toluene (27 g) ('12 g) i (150 m1) Elementary analysis Catalyst Yield State of product C 7: H N (S) .loco '84 Colorless viscous C H O N (1.2 g) a liquid Calcd. 76.00- 10.60 1.71 Found 76.05 10.67 1.80

LiH 87 White powder C H O N "(0.6 g) m.p. 52 54C Calcd. 73.50 9.65 2.14 I Found 72.93 10.04 12.35 Triethylamine 71 1 White wax-like C d- 0 M solid 1 I (50 g) m.p. 31 33C Calcd. 76.91 10.94 1.55 v v Fbund 76.68 10.82 1.51. C,H -,OK 82 White crystals ,C HflQ N (0.8 g) m.p. 99 101C .Cjilcd. 67.01 17.26 3.55 Found 67.44 17.01 3.82 CHQONa 68 Colorless viscous. C H Q N (0.8 g). liquid Calcd. 73.22 16.27 2.37

. Found 72.18 15.8 9 2.41 p'Toluene- 75 White crystals C H O N sulfonic acid m.p. 120- 123C Calcd. 73.76 I 9.75 2.10 (1.5 g) Found 73.52 9.63 2.18

Elementary analysis: C H (7r) N Calculated for C HQJOQN; 74.15 9.58 1.44 Found: 73.90 9.74 1.45

. Note Y EXAMPLE 2 4 9 To a solution of 24.5 g of N-octyldiisopropanolamine n Y in 20 g of triethylamine and 100 g of benzene, 64 g of HO 2 2 fi-(3,5-di-tert-butyl-4-hydroxypheny-l)propionic acid t C F chloride in ml of benzene was added dropwise at 0 3,920,729 7 .8 Y CH CH J N-Lauryl-N,N-b1s.-[B-(3,5-d1-tert-butyl-4-hydroxy- 2 CH2+ phenyl)propionyl]diethanolamine OH K N-Methyl-N,N-bis-[B-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl] diethanolamine 5 L 2,6-Di-tert-butylrp-cresol 5= O CH Ca M 4,4'-Butylidene-bis-(6-tert-butyl-3-methylphenol) I N l,3,5-Trimethyl-2,4,6-tris-(3,5di-tert-butyl-4- hydroxybenzyl)benzene O n-Octadecyl-3-( 3,5-di-tert-butyl-4-hydroxy- EXAMPLES 9 l5, COMPARATIVE EXAMPLES l 12 phenyl)propionate P Tetrakis[methylene-(3,5-di-tert-butyl-4-hydroxy- Resin compositions comprising 100 parts of polyprophenyl)cinnamate] methane pylene powder and 0.5 parts of stabilizers as listed in Q 4,4'-Thiobis-(6-tert-butyl-3-methylphenol) I Table 2 were prepared by dissolving a stabilizer in ace- R 1.1 ,3-Tris(2-methyl-4-hydroxy-5-tert-butyltone, suspending polypropylene powder in the solvent, phenyl)butane and removing the acetone. The resulting resin composi- Table 3 tions were heated at 210C for 4 minutes and during the last 1 minute a pressure of 160 kg/cm was applied Stabilizer Days required Days required thereon to obtain sheet 1.0 mm in thickness. From each I Kind Pa :g iz f 'l y sheet, about 2 g of sample was taken. Each sample was placed on a watch glass and allowed to stand in an air Example 3 a 8'2 2% 2g circulation thermostat controlled at 150C to examine 11 c 05 68 71 the brittleness and weight loss of the sample due to g 8-; 2; 2 thermally oxidative degradation. 14 F 54 62 The results obtained were as shown in Table 3. 15 G 05 54 64 Table 2 (Listof stabilizers) 35,13 1 H 05 45 50 (Compounds of the formula (I) g 8'; 2g 22 A N,N,N-Tri s-[,B-(3,5:di-tert-butyl-4:hydroxyg f g; i phenyl)propionyl] trnsopropanolamme 6 M 0.5 4 4 B N-Octyl-N,N-bis-[B-(3,S-tert-butylA-hydroxyg 8-; j; jg phenyl)propionyl] diisopropanolamine 9 P 05 45 50 C N-Lauryl-N,N-bis-[B-(3,5-di-tert-butyl-4-hydroxy- F 3 g; 2 phenyl)propionyl] diisopropanolamine 12 Non; 1 1 D N-Stearyl-N,N-bis-[B-(3,5-di-tert-butyl-4-hydroxy- N Ole phenyl)proplonyll dusopropanolamlne 1: Days required for retaining 95% of the original weight.

E N-Methyl-N,N-bis-[ B-( 3,5-di-tert-butyl-4-hydroxyphenyl)propionyl] diisopropanolamine F y -[B-( y y EXAMPLES l6 22, COMPARATIVE EXAMPLES phenyl)propionyl] diisopropanolamine 13 22 G N,N-Dioctyl-N-[,B(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]monoisopropanolam Using a procedure similar to that described in Example 9, resin compositions containing 100 parts of poly- Known compounds propylene and stabilizers as listed in Table 4 were pre- H N,NN tris [fi (3,5 di ten butyl 4 hydroxy pared. Synergistic stabilizing effects of a combined staphenynpmpionyn triethanolamine bili zers were examined using the same method that de- I N Butyl NN biS [B(3,5 di tert butyl 4 hydroxy scribed in Example 9. The results obtained were as phenyl)propionyl] diethanolamine Shown m Table Table 4 Days re- Days re- Stabilizers quired to quired for No. brittleretaining Kind Part Kind Part ness weight Example 16 A 0.25 S 0.25 74 78 Comparative Example 13 H 0.25 S 0.25 48 55 l8 M 0.25 S 0.25 8 l0 21 P 0.25 S 0.25 50 S5 22 None l 1 Note) S is disteurylthio diprupionale.

EXAMPLES Z3 29, COMPARATI-VQEJEXAMPLES i- "'l'zi According to the manner similar to that of Examples 9 l5, resin compositions were preparedto examine the stability/provided that 100 parts of unstabilized high density polyethylene powder wasrused in place of the propylene, andthe compositions were heated at' 160C for 5'min utes and during the last 1 minute-a pressure ,of 100 kg/cm was applied to obtain each sheet 0.5 mm in thickness. Each sheet was allowed to stand in an air circulation thermostat controlled at 120C to measure content of carbonyl group'gen'erated due to the thermally oxidative degradationby means of'an infrared absorption spectrum measuring apparatus. The time when the'firsti'e'marka'ble increase of carbonyl group (1,200 to 2,000 cm) was observed is expressed in terms of time ofcarbonylig'ioup-The results are as shown in Table 5.- w

Tablefi-conti-nued t v I Stabilizer A Time of carbonyl No. Kind Part group (hrs) 27 L 012 I 28 M 0.2 200 29 N 0.2 900 O 0.2 L000 31 P 0.2 l.lOO 32 O 0.2 300 33 R 0.2 700 34 Blank 40 1O EXAMPLES 30 33, COMPARATIVE EXAMPLES A mixture of parts of polyvinyl chloride, 1.0 part of l'ead-stearate, 0.5 part of barium 'stearate, 0 5 part of cadmiumstearate and 0.1partj-of a stabilizerwasmixed 20 as shown in Table 6.

5 in a rollat C for 5 minutes, and-pressed at;,l80 C for 5 minutes under 100 kglcm to obtain sheet 1 .0mm in thickness. The colorationof the sheet was exam ed at C-using Gears oven instrument. The results-are Table 6 a Table 5 Stabilizer Time of carbonyl No. Kind Part group (hrs.)

Example 23 A 0.2 2,100

Comparative 23 H 0.2 1,200 Example 24 l 0.2 700 COMPARATIVE EXAMPLES EXAMPLES 34 37,

v A mixture of 100 parts of acrylonitrile-butadiene-styrene copolymer (ABS resin) and 0.3 part of a stabilizer was pressed at C for 10 minutes under 160 kg/cm to obtain sheet 1.0 mm in thickness.

The' coloration of the sheet was examined at 200C using Gears oven instrument. The results are as shown in Table 7.

Table 7 No. Stabilizer 30 min. 60 min. 120 min.

Example 34 A 0 35 B (2 0 36 c 0 37 F O 0 Comparative 41 H O X Example 42 l O O X 43 l. O X X X 44 M O O X 45 P X 46 Blank X X X X X Note:

0 colorless O slightly colored X colored X X markedly colored 7 11 EXAMPLES 38 44 To 100 parts of deodorized soy bean oil, 0.05 part of the present stabilizer was added to examine the oxidation stability. Each 20 ml of the soy bean oil taken in a test tube was placed in a thermostat. and was allowed to be bubbled with clear air at 12.5 em /min. With the lapse of time. a value of hydroperoxide was measured using the active oxygen method. The results are as shown in Table 8.

Table 8 Time (hr) Example No. Stabilizer S I mmol/kg mmol/kg mmol/kg 38 A 0.1 6.3 1 1.4 39 B 0.1 7.0 12.3 40 C 0.1 7.4 12.4 41 D 0.1 7.6 12.6 42 E 0.1 8.0 13.4 43 F 0.1 8.2 13.8 44 G 0.1 8.4 14.0

Blank 0.1 34.0 150.4

What is claimed is:'

l. A compound of the formula,

wherein n is an integer of 1 to 3; R is hydrogen or alkyl having one-to 18 carbon atoms and R is alkyl having one to 18 carbon atoms provided that when n is 2, R is not present andwhen n is 3, both R, and R are not present.

2. The compound according to claim 1, wherein n is an integer of 2, and R is alkyl having one to 18 carbon atoms.

3. A compound of the formula, 

1. A COMPOUND OF THE FORMULA.
 2. The compound according to claim 1, wherein n is an integer of 2, and R1 is alkyl having one to 18 carbon atoms.
 3. A compound of the formula, 